While visiting the rather dull, conventional, country home of John and Anna Denman, Mr. Satterthwaite unexpectedly meets Mr. Quin on a narrow road called Harlequin's Lane behind the house. Locally, it's known as Lover's Lane. While exploring the lane, Satterthwaite meets Molly Stanwell and learns that there's to be an entertainment, a masquerade, that evening.Even Satterthwaite can't foresee the impact that Quin will have on the Denmans, and indeed, on himself and everyone present.The short story was previously published in the print anthology 'The Mysterious Mr. Quin'.